A flight test is about adaption. Adapting to new requirements, shifting timelines, or because of failed expectations.
“It’s also about the people who created it — people like the flight test community, the technicians, the scientists, the people who think outside the box to create what people normally would say is impossible,” as said by the Flight Test Museum Foundation Chairman Art Thompson in 2021.
The successful X-35A test program was foundational to getting the first F-35A Lightning II in the air. On Oct. 24, 2000, a test pilot named Tom Morgenfeld flew the X-35A, a concept demonstrator aircraft, during its inaugural flight. Concept demonstrator aircraft are experimental or research and development aircraft, often called an X-plane, and are designed or substantially adapted to investigate emerging flight technologies. Because of the success of the that October flight, Morgenfeld and the test team set in motion the future of today’s most advanced fifth-generation aircraft.
Morgenfeld graduated from the U.S. Naval Academy in 1965 and was designated a naval aviator two years later. Between two fleet tours flying the F-8 Crusader, he earned a master's degree in aeronautical engineering from the Naval Postgraduate School. He joined Lockheed's Skunk Works as a test pilot in 1979, where he flew the F-117 Nighthawk and the YF-22 demonstrator. In 1991, he was named a chief test pilot, and piloted the joint strike fighter, including the first flight of the X-35A.
Morgenfeld was eager and prepared to enter the co*ckpit that day.
“I was certainly excited but was mainly just going over my preparation in my mind. I was confident that I was ready to do my job,” said Morgenfeld. “There were some nerves involved but none of them were related in any way to my personal safety or a lack of confidence in the design and construction of the airplane. I was totally confident in its design and construction.”
Morgenfeld added that the main source of his concern was that he wouldn’t perform his job well and would subsequently let down his “incredibly talented and dedicated teammates after all their hard work.”
His preparation included performing dynamic accelerations and decelerations as well as engine runs at full military power (maximum thrust without the afterburner) and full power with the afterburner.
The mission was to fly from Air Force Plant 42 in Palmdale, California, to Edwards Air Force Base, California.
Morgenfeld completed the flight mission using just over 2,000 feet of runway to take-off before climbing to 10,000 feet with the gear down. The X-35A tested air vehicle performance and handling characteristics.
According to Morgenfeld, the requirements for a successful first flight are virtually the same for all new airplanes.
“The main thing is to get the airplane airborne, take some worthy pictures, and then get it back safely on the ground,” he said. "Then, once all the media attention is done, the team can get on with the real flight testing.”
“We actually did have a mildly aggressive profile that included landing gear retraction, a relative rarity in first flights these days,” he said about the test flight. "When I retracted the landing gear, it came up correctly, but the main gear doors didn’t close fully. The subsequent gear extension went perfectly so we continued doing gear down test points.”
“The main requirement, however, was just to get the airplane safely from Palmdale to Edwards.”
Morgenfeld remembered how the X-35A looked and flew like a fighter.
“It was evident to me that the handling qualities of the X-35A were superb. As we progressed through the flight envelope expansion, it also became evident that the airplane was a true performer,” he said.
Flight envelopes specify the operational restrictions necessary for a certain mission or flight phase and indicate the airframe’s absolute “never exceed” limitations.
The flight test team and X-35A didn’t stop there. Following the intense campaign of flight envelope expansion, the X-35A broke the sound barrier Nov. 21, 2000, just 25 hours and 25 flights into its aerial test program. Morgenfeld took off in the X-35A and accelerated to 25,000 feet altitude where it reached Mach 1.05, or more than 800 miles per hour.
“Flying the X-35A was the culmination of my [Skunk Works] career and was memorable for many reasons. Performing any real first flight is most memorable for a test pilot but, for me, there were other reasons as well,” he said.
Among those reasons was the fact that Morgenfeld had worked with many of the X-35 flight test engineers, mechanics, and technicians for years previously on the F-117 and YF-22 programs.
“Over those years I had developed great admiration for their talent, work ethic, and selfless dedication to the team,” said Morgenfeld about the memory. “It was most memorable to go through such a successful demonstration program in the company of people whom I consider to be not only incredibly talented flight testers but simply good friends as well."
Comradery amongst the team of pilots stood out to him.
“We all wanted to fly more but each of the pilots dug in and buried themselves in a total team effort to get the job done,” Morgenfeld said of the chemistry he and the other pilots shared. “Each brought a slightly different experience base to the group, and we all meshed well. I worked on many teams, but I don’t know if I ever was on a more cohesive one than this.”
With its flight testing complete after 28 test flights, the X-35A returned to a nearby facility in Palmdale to be fitted with a shaft-driven lift-fan propulsion system. It was then renamed the X-35B and began ground testing in preparation for its short takeoff/vertical landing demonstrations. The Joint Strike Fighter team said the cultivation of information during the flight tests of the X-35A paved the way for the success of the X-35B and, eventually, the X-35C.
Today the F-35 Lightning II stands out as one of the most, if not the most, sophisticated weapons systems available. It is a powerful force multiplier that enhances all airborne, surface, and ground-based assets in the battlespace. There have been over 840 F-35s delivered to date, 12 nations have declared their fleet operational, and nearly 335,000 sorties have been flown. The F-35 is continuously requested as more countries are actively exploring the procurement of the aircraft for their own air defenses.
“After much hard work developing the weapons system for the F-117, I got to see on TV just how well it performed in Desert Storm,” said Morgenfeld, adding that, as a test pilot, he’s always considered his “ultimate customer” to be the pilot who must fly and fight with the airplane operationally.
“While the X-35A was only the beginning of the F-35’s journey, I’m very happy to have been a small part of that.”
